". . . gesture cannot aid learners simply by providing a second modality. Rather, gesture adds imagery to the categorical distinctions that form the core of both spoken and sign languages."
That research also sheds light on the function of the pedagogical movement patterns (PMPs) of haptic pronunciation teaching work as well. (Several of the gestural patterns closely resemble signs used in American Sign Language, and early development of the system was informed and inspired by ASL, in fact.)
One of the more interesting parallels is the fact that ASL signs of high emotional intensity more often tend to terminate in touch--as do all PMPs. A second is that the PMPs of EHIEP (Essential haptic-integrated English Pronunciation), for the most part, present vivid visual pictures that are learned and recalled easily. If you'd like to learn more, just join us next month in Costa Rica!